Really? This is an immigration advocacy group. What do you expect them to say? Immigration is how they earn their living. They quote the same disagreement that the immigrant researchers did with the Fraser Institute's first report. The Fraser Institute read their rebuttal, examined it, and then, while taking some of it into account, repudiated most of it based on faulty design, and came out with a new report the following year.
You understand that, unlike immigration advocacy groups the Fraser Institute does not have any particular axe to grind or profit to make in coming out with a report on immigration, right?